Pin and bushing lock for die sets



Patented Aug. 22, 1944 UNITED STATES PATENT OFFICE 2,356,387 r g PIN ANDBUSHING LOCK Foit DIE jslrrs Fred 0. Danneman, New York, N. Y.Application December 28, 1942, serial No. 470,333.

16 Claims.

This invention concerns die sets of similar machine elements. Moreparticularly the invention refers to locks and means for securing inposition cylindrical guide parts of those elements, such as the leaderpins or bushings.

Machine elements of that type require accurate alignment of the coactingparts, more particularly when they are arranged to reciprocate inrelation to each other. In a die set that refers to the punch holder andthe die shoe, for instance to bushings and pins mounted upon these partsand slidably engaged upon each other.

The cylinders accurately fit bores in the coacting parts, such as thedie shoeand the punch holder, and are commonly forced in under pressure.In addition locking or setting means are desirable, which fixedly retainthe cylindrical parts at a preferred position or level in the respectivebores.

Such locks represent a source of trouble because they do not evenlyengage and react in retaining the cylinders in the respective bores, andthey are apt to throw the parts out of alignment, either originally orduring operation. For that reason the locks have been frequently madepermanent which is not desirable, because the parts must occasionally betaken apart and the locks should thus be readily disengageable.

The search for a suitable lock has frequently led to complicatedarrangements in the prior.

art which are undesirable from a point of view of handling, using and inan economical respect.

It is the object of this invention to overcome those disadvantages ofthe prior art, to provide a lock which looks and preserves perfectalignment, which is rugged, which permits the parts to be readilyreleased from each other if so desired, and which is of the utmostsimplicity.

This invention has also specific objects. For practical considerationsit is to provide for means assembling the lock with-the cylinder, sothat it may be handled as one with the cylinder before mounting.

According to anotherobject of this invention the mounting is to besimplified.

More details of these and other objects of this invention will belearned from the following description thereof which is to beinterpreted as an illustration, but not in limitation of the invention.

This application'is a continuation in part of my copending application,Serial No. 430,315; for Demountable pin or shank assemblies, filed onFebruary 10, 1942, whichhas general reference to a; deviceof thisinvention. However the said parent application is primarily directedtolresilient lock means whereas resiliency is not necessary in a deviceof this invention.

In the drawing:

Fig. 1 is a rear elevation of a punch holder and die shoe assembled intoa die set by locks of this invention. The die set is cross-sectioned atthe right in a plane through the axis of the leader pins and bushings.

Fig. 2 is a corresponding pictorial top View of l3. Pins l I extend witha close, sliding fit through the bushings I4, which are seated incorrespondingbores P5 of the punch holder H'i.

According to the invention the cylinders, e. g. the pins, or bushings,or both of them, have circular grooves. Into each groove extend in aradial direction a plurality of sectors which substantially complementeach other to form a circular element like a washer or' flange. Thosesectors are directly affixed to the partupon which the respective'grooved'cylinder is to be locked.

In a preferred embodiment my invention also provides a means e. g. acage holding the complementary sectors radially together, thus retainingthem in the groove of the respective cylinder, although they may not yetbe affixed to the part having a bore accommodating that cylinder.

That embodiment is illustrated in Figs. 1 and 2. Sets of complementarysectors I1 and I8 each engage in a groove IQ of one of the leader pins II. Corresponding sets'of sectors 20 and 2| engage in grooves 22 upon thebushings l4. Since in the exemplary showing of the drawing the sets ofsectors are pairs, they are substantially semi-circular or half annuli'.The sectors are suited for direct mounting by being fiat upon one side,so that they are thus shown to affix directly to the top side of the dieshoe l3 and bottom side of the punch holder l6, respectively. If thesectors of a set are made by cutting a washer or flange into two moreparts, they will notnecessarily touch each other, but may be spacedapart to the width of the cut 23.

The grooves l9 and 22 may have any desired their sides which extendnormally to the axis of the respective cylinder, and the sectors haveparallel marginal surfaces which fit exactly between said sides. Thatarrangement avoids any radial components of the thrust between thecylinders and the sectors.

A means encircling the outer periphery of the sectors of each set willretain the sectors in the grooves in which they are centripetallyengaged.

In the embodiment of Figs. 1 and 2 of the drawing, such means isindicated by cylindrical skirt portions and 26 of caps or cages 21 and28, which respectively centripetally retain the sectors I! and I8 inengagement upon the leader pins, and the sectors 20 and 2| in engagementupon the bushings M. The caps or cages 21 and 28 may be attached to thedie shoe l3 and the punch holder l6 together with the sectors retainedthereby, the drawing showing screws 29 for such purpose, which extendinto the caps or cages, through clearance holes in the sectors, and arethreadedly engaged upon the die shoe and the punch holder, respectively.

Each cap or cage has a clearance hole for the respective leader pin orbushing and serves also as a protective covering for the sectors. Thesecaps or cages may be very thin because they are under no particularstress under operating conditions when arranged as shown. Thus they maybe sheet metal stamping, and legends may be struck up in their surfacesin the stamping, as indicated at 30.

Such caps or cages are preferred means for holding together the sectors,because they retain the sectors upon the pins or bushings even beforethese are assembled with the die shoe and punch holder. On the otherhand each set of sectors may also be held together by being countersunk,in whole or in part, into a corresponding recess of the die shoe, or ofthe punch holder, or into the respective bores. When the sectors areretained in part only in a recess, this may refer to their thickness orto any fraction of their diameter or to both. That is illustrated inFig. 3.

In the arrangement of Fig. 3 each one of the sectors 3| and 32 has athinner marginal portion 33, surrounding a thicker central portion 34engaging in groove l9 of the leader pin ll. Those thicker centralportions 34, like the sectors, substantially complement each other tomake an annulus and they fit into a recess 35 in the top side of theshoe '13, so that the sectors 3| and 32 are retained in groove [9, whenstrapped by screws 29 onto die shoe [3, or by groove pins or othersubstitutes for or equivalents of screws. The pair of sectors 36 and 31engaged in the groove 22 of the bushing M of the modification of Fig. 3similarly provide a thinner marginal portion 38 surrounding a heaviercentral portion 39. But in that case the outer diameter of theprojecting part of the central portion 39 is limited to the diameter ofbore I5. In case of this particular arrangement no special recess has tobe provided at all in the surface to which the sectors are affixed, andstill they remain secured in the groove while resting on such surface.

The invention is put to use as follows:

In a device of Figs. 1 and 2 a set of sectors l1 and I8 is inserted inthe groove I9 of a leader pin ll. Cap, cage or stamping 21 is thenslipped onto the leader pin and over the sectors projecting therefrom,so that the sectors are retained in the grooves. The leader pin and thesectors may now be handled as one unit. The leader pin is inserted intothe corresponding bore I2 of the die shoe l3 and is pushed down untilthe sectors come to rest upon the top surface of the shoe. Then the cap21 and the sectors l1 and I8 contained therein are screwed down outsideupon the die holder by screws 29. The bushings are arranged upon thepunch holder l6 by a corresponding operation.

In the embodiment of Fig. 3 the sectors 3i and 32 may be inserted ingroove I9 after the pin H has been inserted in the respective bore l2but just before such pin is finally pushed down to the desired level. Inthis case as well as in the case of the embodiments of Figs. 1 and 2 theholes may be oriented relatively to the cap in the die shoe just beforethe leader pin reaches .the final position or level, e. g. by theninserting the screws 29, and those screws are tightened when the leaderpin l I has been finally allocated. Bushings M are mounted in similarmannen above the punch holder.

In connection with the modifications shown in Fig. 3 it is desirable togather the inserted sectors centripetally until they or their projectingportions, such as the thickened parts 34 or 39, have dropped into thecountersinks, recesses or bores of the respective die shoe or punchholder. It is expedient to use for such purpose a cap like the cages orstampings 21 or 28 of the embodiment of Figs. 1 and 2. That cap is thenremoved after the sectors have dropped into their seat in the respectivesupporting surface, whereupon they are screwed down.

Having thus described my invention in detail, yet I do not Wish to belimited thereby, except as the state of the art and the appended claimsmay require, for it is obvious that various modifications and changesmay be made in the form of embodiment of my invention, without departingfrom the spirit and scope thereof.

What I claim is:

1. In a machine element comprising coacting parts relatively guided by acylinder mounted in a bore of one of said parts, a lock for allocatingsaid cylinder in said bore. on said one part in an axial direction andhaving a plurality of sectors directly screwed onto said part and eachengaged between the sides of a groove encircling said cylinder.

2. In a machine element comprising coacting parts relatively guided by asubstantially rectilinear cylinder mounted in a bore of one of saidparts, a lock for allocating said cylinder in said bore on said one partin an axial direction and having a plurality of sectors directly screwfastened onto said part and extending from all sides into and engaged ina circular groove in said cylinder.

3. In a machine element comprising coacting parts relatively guided by acylinder mounted in a bore of one of said parts, a lock for allocatingsaid cylinder in said bore on said one part in an axial direction andhaving a plurality of complementary sectors directly screw fastened ontosaid part and each engaged between the sides of a groove encircling saidcylinder.

4. A look for endwise allocating in a bore of one of two coacting parts,a cylinder fitting a corresponding bore of one of said parts and guidingsaid other part, a circular groove inthe outside of said cylinder, andsectors fitting said groove and each screw fastened onto said boredpart.

5. A look for endwise allocating in a bore of one of two coacting partsa cylinderrelatively.

registeringly guiding said parts, comprising a groove encircling saidcylinder, sectors fitting said groove and each screw fastened onto saidone part, and circular retaining means radially confining said sectorsin said groove.

,6. A lock for endwise allocating in a bore of one of two coacting partsa cylinder relatively registeringly guiding said parts, comprising agroove encircling said cylinder, sectors fitting said groove and screwfastened onto said one part, and a cage radially confining said sectorsin said groove.

, 7. A lock for endwise allocating in a bore of one of two coactingparts a, cylinder relatively registeringly guiding said parts,comprising a groove encircling said cylinder, sectors fitting saidgroove and screw fastened onto said one part, and circular retainingmeans radially confining said sectors in said groove but withdrawablefrom said sectors in the direction of the axis of said cylinder, saidmeans being screwed onto said one part together with said sectors.

8. A look for endwise allocating in a bore of one of two coacting partsa cylinder relatively registeringly guiding said parts, comprising agroove encircling said cylinder, sectors fitting said groove and screwfastened onto said one part, and a stamping having a substantiallycylindrical skirt radially confining said sectors in said groove.

9. A lock for endwise allocating in a bore of one of two coacting partsa cylinder relatively registeringly guiding said parts, comprising agroove encircling said cylinder, sectors fitting said groove and screwfastened onto said one part, a stamping substantially covering one sideof said sectors where they are outside of said groove, and a skirt onsaid stamping radially confining said sectors in said groove.

10. A lock for endwise allocating in a bore of one of two coacting partsa cylinder relatively registeringly guiding said parts, comprising agroove encircling said cylinder, and sectors fitting said groove andeach screw fastened onto said one part, said one part having a circularrecess in which said sectors are seated.

11. A look for endwise allocating in a bore of one of two coacting partsa cylinder relatively registeringly guiding said parts, comprising agroove depressed into said cylinder, and sectors fitting said groove andeach screw fastened onto said one part, said sectors having projectionsengaged in a recess of said one part.

12. A lock for endwise allocating a cylinder in a bore of a support,comprising a groove encircling said cylinder, and sectors fitting saidgroove and each screw fastened onto said support, said sectors havingrecesses at which they are centripetally engaged by said bore of saidsupport.

13. In a die set, a die shoe, a leader pin engaged in a bore of saidshoe and having a circular groove, and a subdivided flange engaged inand projecting from said groove and fastened upon the surface of saidshoe.

14. In a die set, a punch holder, a bushing engaged in a bore of saidpunch holder and having a circular groove, and a subdivided flangeengaged in and projecting from said groove and fastened upon the bottomside of said punch holder.

15. The method of mounting a cylinder in the bore of a part of a die setby sectors engaged in a groove of said cylinder and adapted to bestrapped onto said part after being dropped into a. recess holding themtogether, comprising retaining the sectors in the groove, engagingthereover a means holding said sectors centripetally together, sinkingthe cylinder into said part until the sectors have dropped thereinto,removing said means, and strapping each sector onto said part.

16. In a lock for endwise allocating upon a support a cylinder having acircular groove upon the outside, sectors substantially complementarilyfitting and fitting around said groove and projecting therefrom, a capcomprising a washer portion clearing said cylinder and a skirt portionextending from said washer portion and adapted to engage peripherallyaround said sectors when they are fitted into and around said groove,part of said washer portion being struck up to form a legend thereon,and fastening means for engaging said sectors upon said support whensaid cap is engaged therearound.

FRED C. DANNEMAN.

